This invention relates generally to a machine and a method for forming and bending tubing, and specifically a machine and a method for manufacturing full crossover fittings and half crossover fittings, both of which have a central bend and at least one cup end.
Older buildings and structures are constantly being renovated. As part of these renovations, new and more complex plumbing is often installed. In many cases, the plumbing pipes or tubes are exposed on either the inside or outside of the building walls. However, due to pre-existing structural constraints and plumbing specifications many tubes must cross over one another, thus, necessitating the use of crossover fittings at these intersections.
Traditionally, crossover fittings are manufactured using a plurality of independent machines and a great deal of manual handling. For example, in one method a tube bender such as a Wallace machine may be used to make an initial 90.degree. bend in a portion of raw tube stock. The raw tube stock is then mounted on an arbor rod containing two linked arbor balls which maintain the tube's inside diameter while the initial bend is created. After the tube is bent, the arbor balls are then retracted approximately 1 inch at which point a circular saw cuts a rough tube section from the raw stock. Within this traditional process, a further step requires a bend former machine where the tube section is loaded into a V-notch die and mandrels are inserted into each end. These mandrels aid in forming the bends near each end of the tube section. The tube section is then moved to a hand punch press machine where punches enter one end of the tube section to expand it against the outside dies, thus forming a cup. Next, the part is placed into another hand punch press machine which sizes the second end of the tube. Finally, the tube section is placed into a two-way facing machine which removes excess material on each end of the tube; the ends are cut and squared up in the facing machine when blades cut the tube around a pilot rod inserted thereinside. At this machine, the inside diameter of the tube cup ends are also chamfered. The full crossover and half crossover fittings can both be manufactured by this process.